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Hematopoietic stem and progenitor cells (HSPCs) are very rare in cord blood (and in other cell sources such as bone marrow and mobilized peripheral blood). For many applications it is important to obtain HSPC preparations that are relatively free of mature cells. EasySep™ column-free immunomagnetic cell isolation may be used to either deplete mature blood cells resulting in a sample enriched for untouched CD34+ cells, or to directly select for CD34+ cells resulting in a sample with a higher purity of HSPCs. This should effectively deplete erythroblasts as these do not express CD34, but do express mature blood cell markers, such as glycophorin-A. Alternatively, standard density gradient centrifugation may be combined with RosetteSep™ selection to enrich for lineage marker-negative (Lin-) cells by depleting mature blood cells and their immediate precursors, including erythroblasts. You can also combine negative and positive selection methods (i.e., RosetteSep™ pre-enrichment followed by EasySep™ positive selection of CD34+ cells) to achieve the highest possible CD34+ cell purity from whole cord blood. For more information, please read our technical bulletin on the isolation of CD34+ cells from human cord blood. Purified CD34+ cells can be used directly in culture, or purified further by fluorescence-activated cell sorting (FACS) to isolate subsets of CD34+ cells that are more highly enriched for hematopoietic stem cells or immature progenitor cells.